Closure device for container openings



Aug. 26, 1.941,

Filed July 14, 195

4 V I, fl I X INVENTOR.

/ HwqpdZM fiaisorz BY T gfyC- C E A ORNEY.

Patented Aug. 26, 1941 Howard W. Dodson, Philadelphia, l"a., asslg'nor,by mesne assignments, to United Steel Barrel Company, Philadelphia, Pa.,a corporation of Pennsylvania Application July 14, 1939,: Serial No.284,463

4 Claims.

The present invention relates to closure devices for openings in metalcontainers, such as drums, barrels, cans, tanks, or the like, andparticularly for openings through which such containers,

drums, barrels, cans, tanks, etc. may be filled which the inventionconsists can be variously arranged and organized and that the inventionis not limited to the precise arrangement and organization of theinstrumentalities as herein and emptied. The present invention relatesmore particularly to container openings and closure devices thereforwhich are to be repeatedly opened and closed.

The'cost of production of closure devices for container openingsislfrequently a vital factor bearing upon the practicability of thedevices,

particularly where the containers, such as the sheet-metal drums,barrels, cans, tanks, or the like are likely to be used only once forthe transportation or storage of the original contents and it istherefore important to provide not only effective closure means havingsuflicient structural strength, but also closure means which an beproduced at low cost, and which can be m de uniform by manufacturingoperations not subject to failure. Since such closure devices must bemade in large quantities, it is important that the construction shall beone which will be dependable in mass production.

Among the objects of the present invention is the provision of strongand durable closure means for sheet-metal containers, such as drums,barrels, cans, tanks, etc. which ,will be dependable and which may beproduced at low cost, and in which the possibilities of failure, eitherin the manufacture or in the use thereoL-are minimized.

of the container.

shown and described.

lngthe accompanying drawing, wherein like reference characters indicate.like parts,

Figure 1 represents a fragmentary view, partly in section and partly inelevation, of a drum head opening and closure means thereforconstituting one embodiment of the present invention.

Figure 2 represents a bottom plan view of said drum head opening andassociated closure means, as would be-seen for instance on line 22 ofFigure 1 looking in the direction of the arrows.

Figure 3 represents a perspective view, on a somewhat reduced scale, ofthe removable screwthreaded closure plug shown in Figure 1 disassociatedfrom the rest of the device.

According to the present invention, a hole or opening,,indicatedgenerally by the numeral I0, isformeddn the sheet-metal of the head orbody Inthe particular illustration shown, the body sheet-metal or bodymetal H is indicated as being that of the head or generally flat end ofa sheet-metal container, such as a With the above and other objectsinview'which will appear more fully from the following detaileddescription, accompanying drawing. and

appended claims, the present invention contemplates anoutwardly-projecting flange at the opening. of a sheet-metal container,said flange being formed integrally with the body metal of the containerand externally reinforced by a fixed; cast band enveloping said flange,said remforcing band being cast in situ in a molten state'from a metalseparate and distinct and different'from the body metal of thecontainer.

The present invention furtherconsists of other I novel features andprinciples and details of construction, all of which will appear morefully from the following detailed description, elccompanying drawing andappended claims. 7

For the purpose of illustrating the invention, there is shown in theaccompanying drawing one form thereof which is at present preferred,since the same ,has been found in practice to give satisfactory andreliable results, although it is to-be understood that variousinstrumentalities of 55 the container. Thus, in accordance with thebarrel, can, tank, etc.,'although it is to be expressly, understood thatthe present invention is equally applicable to openings formed in themore or less cylindrical sides of such containers.

The body metal at. the zone of the opening is l stan ped or pressedoutwardly to form a generally .cyl drical outwardly-extending neck orflange l2, d in the illustrated embodiment of the present inventidn theouterl marginal portion of this neck It is turned down to provide aperipheral gasket-seating end-flange ii.

A screwthread of any desired pitch and outline, as for instance, thecoarse rounded screwthread It illustrated in the drawing, may be,

rolled, turned, pressed or otherwise formed along the side of, thecylindrical flange l2, thereby'to provide securement cans for acorrespondi'nglythreaded closure plEE l5. If desired, the-pitch of thethread It may assume a form other thanthe curved form illustrated.-Thus, tlre fnumber of threads per inch may be increased or decreasedmaking the thread i4 finer or coarser; and the shape thereof may assumea sharp V-shaped or other forms.

This screw-threaded flange I 2 is snugly encircled by a reinforcing bandor shell 16 which is cast in situ from molten metal separate anddistinct and different from the body metal' of varied, and the threadmay present invention, a mold having a concavity or a metal-receivingspace corresponding in size to the desired cross-section of the ultimatereinforcing band is applied over the outwardly-extending screw-flangel2, with the flange acting as a core within said mold.

The particular construction of themold and the manner of its applicationto the container screw-flange is not shown here, because thisspecification is intended to be addressed to the resultant product andthe method of making the same, and not to the apparatus for practicingthe method or making [the product.

A relatively low melting point alloy, consisting principally of zinc,with variable amounts of aluminum, copper and magnesium, and,optionally, with some percentages of tin and antimony is then poured orforced into the mold under pressure in a molten state, and at atemperature sufficiently high to insure that the metal alloy will flowfreely and will completely fill .all the unoccupied space in said mold.

A suitable low melting point alloy composition for the flange-encirclingband It 'may be repre sented by a composition of ninety to ninety-fiveper cent zinc and about five per cent aluminum, one to four per centcopper and about .01 to .05

' per cent magnesium. These proportions may be varied according to thedegree of hardness and other qualities desired.

As the molten metal hardens around'the screwflange l2, it becomes fixedrelative thereto, and

the casting I6 is prevented from being rotated 1 thereon, or movedaxially therealong. Thus, since the cast reinforcing band l6 closelyfollows the external contour of the screw-thread |l along the side ofthe screw-flange l2, and since the band I6 is further axially confinedbetween the juxtaposed end-flange I3 and the body metal H at the base ofthe screw-flange, rotary and/or axial movement of this band isprevented.

Prior to the application of the molten metal to form theflange-reinforcing band 5, the body metal, at least in the zone of theapplication of the molten metal, is preferably cleaned of all scale. Inthis manner, substantial adhesion or union or metal-to-metal bonding maybe obtained between the molten metal and the body metal. This union orbonding may be further "augmented or increased by initially turningorcoating or platingthe bodymetal with cadmiumor zinc in. the zone wherethe molten metal is to be applied.

If desired, any suitable additional means may be provided for furtherpreventing or restraining the flange-reinforcing band or shell Hi fromrotating or becoming loosened on the screwflange l2. Thus, for example,anti-rotational surface irregularities may be formed in the containerbody metal surrounding the base of the screw-flange 12. Thus, an annularzone of the body metal disposed at the'base of the screwflange l2, maybe pressed, stamped or otherwise shaped into corrugated or undulatingform, to.

provide radially extending alternate ridges I1 and troughs l8. As themolten metal from which the reinforcing band I6 is cast is forced intothe molding, it enters into and fills the troughs l8 and accordinglywhen the casting l6 subsequently hardens it will be further restrainedfrom rotating on the neck |2.

The container wall around the screw-flange |2 may be structurallystrengthened, if desired, by an annular ridge or raised portion I! whichmay be provided by slightly off-setting the annular zone at the base ofthe flange I2 outwardly or inwardly relative to the contalnerwall II.

In the illustrated embodiment of the present invention the reinforcingband, I6 is cast with a generally fiat annular end-surface 20 disposedin the same plane as the gasket-seating surface of the end-flange l3 andindeed in direct continuation thereof, thereby providing a relativelywide smooth and uninterrupted gasket-seating surface. A sealing gasket2| is pressed down onto the seating surfaces l3 and 20 by theclosureplug l5, which is itself provided with an annular gasket-seatingsurface 22 in juxtaposition with the screw-flange end-surface l3. 'Inuse, the sealing gasket 2| is operatively compressed as the screw-plugI5 is screwed into the screwflange l2. 1

By providing a gasket-seat onthe body metal comprising the end-flangelit, the fluid-tight seal established when the gasket 2| is pressed downthereover will not be affected by any possible cracking or fracture ofthe die-cast flangeencircling band It. Thus, for instance, the cast bandl6 may become fractured or cracked anywhere along its periphery, and mayeven be completely broken through at one or more points, withoutaffecting the seal established by the gasket 2|, because the gasket ispressed directly against the continuous and uninterrupted body metalsurface IS.

The screw-threaded closure plug I5 may be inexpensively constructed bybeing stamped or .pressed out of blanks of suitable sheet-metal,

preferably of heavier gauge than the container body metal. Theparticular closure-plug illustralted in the drawingis of hollowconstruction, and is provided at its upper end with polygonalseizure-means 23 adapted to be seized or engaged and turned by anysuitable wrench or tool, thereby to tighten or loosen said plug.

After the plug l5 has been screw-threadedly engaged withthescrew-fiangel2 and tightened, a tamper-indicating sheet-metal sealing cap 24 may besuperimposed over the plug with its peripheral edge portion 25 crimpedor turned under the band shoulder 26, so as completely to prevent accessto the plug it during transportation or storage of the container. Inremoving the tamper-indicating sealing cap 24, the crimped-flange 25thereof is, so distorted as to 'make reapplication' of the Y sealing capimpossible without detection.

ing,. and the thread bearing portion of the body metal is structurallyreinforced by the encircling band cast in situ. Accordingly, the closuredevice of the present invention possesses structural strength anddurability far in excess of that ohtainable from the mere use. of ascrew-flange formed directly out of the container sheet-metal,

particularly where the container sheet metal is relatively thin, as isfrequently the case. Thus, the hereinabove described constructionprovides strong and efiective container. closure means which directlyutilizes the body metal of the container to anchor the removable plug,and which does not depend on separate thread-bearing flanges or bushingsfor structural strength and which'is yet very strong and durable evenwhen the particular sheet-metal from which the container is formed isrelatively thin.

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof, and it istherefore desired that the present embodiment be considered in allrespects as illustrative and not restrictive, reference being had to theappended claims rather than to the foregoing description to indicate thescope of the invention.

Having thus described the invention, what is hereby claimed as new anddesired to be secured by Letters Patent, is:

1. In a sheet metal container of the character described, a sheet metalpanel having an opening' therein bounded by an integral outwardlyextending generally cylindrical annular flange,

the longitudinal axis of said flange being generally perpendicular tothe plane of said panel at the base of the flange, the wall'of saidflange being helically corrugated and having its inner surface adaptedfor direct screw-threadeden- V gagement with the threaded outer surfaceof .a

closure plug, the outer end portion of said flange being turneddownwardly into juxtaposition with the panel metal surrounding the basalportion of said flange, and a relatively thick annular flangereinforcingband of a lower melting point metal, cast in situ, extending aroundsolely the outer surface of said flange and reaching from the and snuglyfilling the troughs or said corrugationsQwhereby said cast band isnon-rotatable panel metal at the base of said flange to the juxtaposeddownturned outer end portion of said flange, the metal of said cast bandextending into and snugly fllling the troughs of said helicalcorrugations in the flange wall, whereby said cast band is non-rotatablerelative to said flange and snugly backs said flange in a zone generallycoextensive with its zone of screw-threaded engagement with said closureplug therebymaterially relative to said flange and snugly backs saidflange in a zone generally coextensive with the zone of engagementbetween said flange and said closure plug thereby materiallystrengthening said flange around said zone, said cast band beinggenerally confined to the immediate vicinity of the panel opening, butnot extending thereinto.

3. In a sheet metal container of the character described, a sheet metalvpanel having an opening therein'bounded by an integral outwardlyextending generally cylindrical annular flange, the outer end portion ofsaid flange being turned downwardly to provide a generally flat annularsurface, and an annular flange-reinforcing band,-

cast in situ of a lower melting point metal, encircling said flange,said cast band including a generally flatannular end surface co-planarwith andin direct continuation of the aforesaid annustrengthening saidflange around said zone, said 7 cast band being generally confined tothe immediate vicinity of the panel opening, but not extendingthereinto.

2. In a sheet metal container of the character described, asheet metalpanel having an opening therein bounded by an integral outwardlyextending generally cylindrical annular flange, the iongitudinal axis ofsaid flange being generally perpendicular to the plane of said panel atthe base of said flange, the inner surface of said annular flange beingadapted for intimate direct engagement with the outer surface of aclosureplug adapted to receive a sealing gasket.

lar surface, said co-planarannular surfaces compositely'providing-agenerally flat gasket seat 4. In a sheet metal container of thecharacter described, "a metal panel having an openingtherein bounded byan outwardly extending generally cylindricalflange having itslongitudinal axis generally perpendicular to the plane 'of the panel atthe base'of said flange, a cast reinforcing band. cast in situ of alower melting point metal, enclrcling said flange and in continuousintimate contacttherewiththroughout theirzone 1 ofoverlap, said castreinforcing band including a well-defined shoulder extending around theoutersurface of said band over which the lower skirt portion of asheetmetal sealing capmay be crimped to anchor said cap to said cast band.

HOWARD W.'DODSON.

